In the Russian language there are many verbs with a particle -СЯ at the end. This particle is called a reflexive postfix, and verbs with this postfix are called "reflexive verbs". All reflexive verbs are intransitive , that means that after them the Accusative case is not used without.
For several centuries, Russia had a lot... good and very bad moments. But there were periods that are difficult to forget and which need to be remembered, talked about. This, for example, January 27, 1944 is the day of lifting the blockade of the city of Leningrad.
Prepositions are words that connect words in phrases and sentences. There are many prepositions in the Russian language. They do not change, but the word after the prepositions change in cases. Prepositions can have meanings of place, time, purpose, reason, and others.